Question

这个函数在我的数据库中搜索记录。除了 if 条件之外，即使条件为真，else 语句（“未找到记录”）也会继续执行。 OUTPUT screenshot

def displaySearchAcc():
try:
    command = "SELECT * FROM BANK"
    mycursor.execute(command)
    s = mycursor.fetchall()
    ch = input("Enter the account number to be searched : ")
    for i in s:
        i = list(i)
        if i[0] == ch:
            print("*" * 125)
            print("ACCNO", "NAME", "MOBILE", "EMAIL", "ADDRESS", "CITY", "COUNTRY", "BALANCE")
            print("=" * 125)
            for j in i:
                print("%14s" % j, end=' ')
                print()
        else:
            print("record not found")
except:
    print("Table not found")

Answer 1

def displaySearchAcc():
try:
    command = "SELECT * FROM BANK"
    mycursor.execute(command)
    s = mycursor.fetchall()
    ch = input("Enter the account number to be searched : ")
    for i in s:
        if i[0] == ch:
            print("*" * 125)
            print("ACCNO", "NAME", "MOBILE", "EMAIL", "ADDRESS", "CITY", "COUNTRY", "BALANCE")
            print("=" * 125)
            for j in i:
                print("%14s" % j, end=' ')
                print()
        else:
            print("record not found")
except:
    print("Table not found")

Answer 2

你甚至不需要 for 循环。您可以仅使用 SQL 语句执行搜索，这比您使用的迭代方法快得多。假设列名是 account_number

def displaySearchAcc():
    account_no = input("Enter the account number to be searched : ")
    command = f"SELECT * FROM BANK WHERE account_number = '{account_no}'"
    row = mycursor.fetchone()
    if row is not None:
        print("*" * 125)
        print(
            "ACCNO", "NAME", "MOBILE", "EMAIL", "ADDRESS", "CITY", "COUNTRY", "BALANCE"
        )
        print("=" * 125)
        for col in row:
            print("s" % col, end=" ")
            print()
    else:
        print("Record not found")

如果您真的坚持使用迭代方法，那么您所犯的错误就是行i = list(i)。 i 已经是一个列表，通过将 i 放入列表中，您正在制作列表（二维列表），这会扰乱您的迭代。

def displaySearchAcc():
    try:
        command = "SELECT * FROM BANK"
        mycursor.execute(command)
        all_rows = mycursor.fetchall()
        account_no = input("Enter the account number to be searched : ")
        for row in all_rows:
            if row[0] == account_no:
                print("*" * 125)
                print("ACCNO", "NAME", "MOBILE", "EMAIL", "ADDRESS", "CITY", "COUNTRY", "BALANCE")
                print("=" * 125)
                for col in row:
                    print("%14s" % col, end=' ')
                    print()
                break; # No need to iterate further
        else:
            print("record not found")
    except:
        print("Table not found")

另外，使用更好的变量名。

Else 语句继续执行 PYTHON

2 个答案: